Multiple lead electrode probe for controlled tissue ablation

Abstract

Tissue regions are treated using a multiple lead electrode probe. A plurality of electrodes may be disposed about an elongate shaft. The elongate shaft may be slidably disposed within a lumen of a delivery sheath. One or more probes including one or more electrically active regions may also be slidably disposed within the delivery sheath. The one or more probes may be configured to extend radially about the elongate shaft. The plurality of electrodes and the electrically active regions may be individually connected to a control and power unit through individual channels.

What is claimed is: 
     
       1. A tissue ablation system, comprising:
 a delivery sheath having a proximal end, a distal end, and a lumen extending therebetween; 
 an elongate shaft having a proximal end and a distal end slidably disposed within the lumen of the delivery sheath; 
 a plurality of helical members disposed about the elongate shaft, the plurality of helical members including a first helical member and a second helical member distinct from the first helical member, the plurality of helical members defining at least one helically wound electrode; 
 wherein the first helical member and the second helical member axially overlap; 
 one or more probes slidably disposed within the delivery sheath; and 
 at least one electrically conductive region on the one or more probes. 
 
     
     
       2. The tissue ablation system of  claim 1 , wherein the one or more probes are configured to transform from a collapsed configuration to a radially expanded configuration when the one or more probes are distally advanced beyond the distal end of the delivery sheath. 
     
     
       3. The tissue ablation system of  claim 2 , wherein the one or more probes comprises a shape memory alloy. 
     
     
       4. The tissue ablation system of  claim 3 , wherein the one or more probes comprise an insulating coating disposed over the shape memory alloy. 
     
     
       5. The tissue ablation system of  claim 4 , wherein the at least one electrically conductive region on the one or more probes are regions of the probe free of the insulating coating. 
     
     
       6. The tissue ablation system of  claim 1 , wherein the one or more probes are individually actuatable. 
     
     
       7. The tissue ablation system of  claim 1 , wherein the at least one helically wound electrode and the at least one electrically conductive region on the one or more probes are electrically connected to a power and control unit through individual channels. 
     
     
       8. The tissue ablation system of  claim 1 , wherein a distal end region of the one or more probes comprises a spear-like shape. 
     
     
       9. The tissue ablation system of  claim 1 , wherein the one or more probes comprises a helically wound filament. 
     
     
       10. A tissue ablation system, comprising:
 a delivery sheath having a proximal end, a distal end, and a lumen extending therebetween; 
 an elongate shaft having a proximal portion and a distal portion, the elongate shaft slidably disposed within the lumen of the delivery sheath; 
 a first helical member defining a first helically wound electrode disposed about the distal portion of the elongate shaft, the first helically wound electrode having a first length; 
 a second helical member defining a second helically wound electrode disposed about the distal portion of the elongate shaft, the second helically wound electrode having a second length less than the first length; 
 wherein the second helical member is structurally distinct from the first helical member; 
 wherein the first helical member is at least partially nested with the second helical member; 
 a third helical member defining a third helically wound electrode disposed about the distal portion of the elongate shaft, the third helically wound electrode having a third length less than the second length; 
 a plurality probes slidably disposed within the delivery sheath, the plurality of probes configured to move between a compressed configuration and an expanded configuration; 
 at least one electrically conductive region on each of the probes of the plurality of probes; and 
 a power and control unit in electrically communication with the first helically wound electrode, the second helically wound electrode, the third helically wound electrode, and the at least one electrically conductive region on the each of the probes of the plurality of probes. 
 
     
     
       11. The tissue ablation system of  claim 10 , wherein the at least the first helically wound electrode, the second helically wound electrode, the third helically wound electrode, and the at least one electrically conductive region on the each of the probes of the plurality of probes are electrically connected to the power and control unit through individual channels. 
     
     
       12. The tissue ablation system of  claim 10 , wherein each of the probes of the plurality of probes is individually slidable within the delivery sheath. 
     
     
       13. The tissue ablation system of  claim 10 , wherein plurality of probes are configured to transform from a collapsed configuration to a radially expanded configuration when the one or more probes are distally advanced beyond the distal end of the delivery sheath. 
     
     
       14. The tissue ablation system of  claim 13 , wherein the plurality of probes comprise shape memory alloy and an insulating coating disposed over the shape memory alloy. 
     
     
       15. The tissue ablation system of  claim 10 , wherein the distal portion of the elongate shaft comprises a piercing element.